diff --git a/Tests/test_image_mode.py b/Tests/test_image_mode.py
index 26266611d..345c0dacb 100644
--- a/Tests/test_image_mode.py
+++ b/Tests/test_image_mode.py
@@ -42,7 +42,7 @@ class TestImageMode(PillowTestCase):
             self.assertEqual(signature, result)
         check("1", "L", "L", 1, ("1",))
         check("L", "L", "L", 1, ("L",))
-        check("P", "RGB", "L", 1, ("P",))
+        check("P", "P", "L", 1, ("P",))
         check("I", "L", "I", 1, ("I",))
         check("F", "L", "F", 1, ("F",))
         check("RGB", "RGB", "L", 3, ("R", "G", "B"))
diff --git a/Tests/test_image_putalpha.py b/Tests/test_image_putalpha.py
index 7b66b8833..702afb995 100644
--- a/Tests/test_image_putalpha.py
+++ b/Tests/test_image_putalpha.py
@@ -28,6 +28,13 @@ class TestImagePutAlpha(PillowTestCase):
         self.assertEqual(im.mode, 'LA')
         self.assertEqual(im.getpixel((0, 0)), (1, 2))
 
+        im = Image.new("P", (1, 1), 1)
+        self.assertEqual(im.getpixel((0, 0)), 1)
+
+        im.putalpha(2)
+        self.assertEqual(im.mode, 'PA')
+        self.assertEqual(im.getpixel((0, 0)), (1, 2))
+
         im = Image.new("RGB", (1, 1), (1, 2, 3))
         self.assertEqual(im.getpixel((0, 0)), (1, 2, 3))
 
diff --git a/src/PIL/Image.py b/src/PIL/Image.py
index 4626497fb..1759c7790 100644
--- a/src/PIL/Image.py
+++ b/src/PIL/Image.py
@@ -247,7 +247,7 @@ _MODEINFO = {
     "L": ("L", "L", ("L",)),
     "I": ("L", "I", ("I",)),
     "F": ("L", "F", ("F",)),
-    "P": ("RGB", "L", ("P",)),
+    "P": ("P", "L", ("P",)),
     "RGB": ("RGB", "L", ("R", "G", "B")),
     "RGBX": ("RGB", "L", ("R", "G", "B", "X")),
     "RGBA": ("RGB", "L", ("R", "G", "B", "A")),
@@ -1559,7 +1559,7 @@ class Image(object):
 
         self._ensure_mutable()
 
-        if self.mode not in ("LA", "RGBA"):
+        if self.mode not in ("LA", "PA", "RGBA"):
             # attempt to promote self to a matching alpha mode
             try:
                 mode = getmodebase(self.mode) + "A"
@@ -1568,7 +1568,7 @@ class Image(object):
                 except (AttributeError, ValueError):
                     # do things the hard way
                     im = self.im.convert(mode)
-                    if im.mode not in ("LA", "RGBA"):
+                    if im.mode not in ("LA", "PA", "RGBA"):
                         raise ValueError  # sanity check
                     self.im = im
                 self.pyaccess = None
@@ -1576,7 +1576,7 @@ class Image(object):
             except (KeyError, ValueError):
                 raise ValueError("illegal image mode")
 
-        if self.mode == "LA":
+        if self.mode in ("LA", "PA"):
             band = 1
         else:
             band = 3
diff --git a/src/libImaging/Convert.c b/src/libImaging/Convert.c
index 39ddf8721..ff78555d2 100644
--- a/src/libImaging/Convert.c
+++ b/src/libImaging/Convert.c
@@ -1018,6 +1018,8 @@ frompalette(Imaging imOut, Imaging imIn, const char *mode)
         convert = p2l;
     else if (strcmp(mode, "LA") == 0)
         convert = (alpha) ? pa2la : p2la;
+    else if (strcmp(mode, "PA") == 0)
+        convert = l2la;
     else if (strcmp(mode, "I") == 0)
         convert = p2i;
     else if (strcmp(mode, "F") == 0)